In U.S. Pat. No. 4,030,424 assigned to the same assignee as the present application, a railway car truck is disclosed having a pair of transversely spaced side frames joined by a transverse plate rigidly connected to the lower portion of each side frame to maintain the truck in tram. A bolster including a center bearing extends between the side frames and rests upon spring groups located in vertical slots in the side frames. The weight of the car body is taken on the bolster above the spring groups.